1. Field of the Invention
The present invention relates to a method for manufacturing a hair clipper blade.
2. Discussion of the Background
An edge cutting method using a grindstone 30, shown in FIGS. 22(a)–22(c), is conventionally known as one typical example of methods of manufacturing a hair clipper blade 1′ for use in a manual or electric hair clipper. In FIG. 22(a), β denotes an angle of the grindstone 30 and θ2 denotes an edge cutting angle. Also, γ in FIG. 22(b) denotes an edge groove angle, and θ3 in FIG. 22(c) denotes a tip angle of a cutting edge portion 4.
To increase sharpness of the hair clipper blade 1′, the edge cutting angle θ2 must be finished into an acuter angle. This solution, however, reduces the thickness of a remaining wall of a tip 4a and lowers the intensity of the hair clipper blade 1′. Another problem is that because the amount to be cut by the grindstone 30 is also increased, the life of the grindstone is shortened and the blade cost is pushed up.
In view of those problems, as another example of the related art, Japanese Unexamined Patent Application Publication No. 64-49596 discloses a hair clipper blade 1″ in which, as shown in FIG. 23, a tip angle of the cutting edge portion 4 is formed in two steps as denoted by θ and θ′ to increase both edge sharpness and tip strength. The contents of this application are incorporated herein by reference in their entirety.